Advancing Santorini’s tephrostratigraphy: new glass geochemical data and improved marine-terrestrial tephra correlations for the past ~360 kyrs

The island of Santorini in the Aegean Sea is one of the world’s most violent active volcanoes. Santorini has produced numerous highly explosive eruptions over at least the past ~360 kyrs that are documented by the island’s unique proximal tephra record. However, the lack of precise eruption ages and comprehensive glass geochemical datasets for proximal tephras has long hindered the development of a detailed distal tephrostratigraphy for Santorini eruptions. In light of these requirements, this study develops a distal tephrostratigraphy for Santorini covering the past ~360 kyrs, which represents a major step forward towards the establishment of a tephrostratigraphic framework for the Eastern Mediterranean region. We present new EPMA glass geochemical data of proximal tephra deposits from twelve Plinian and numerous Inter-Plinian Santorini eruptions and use this dataset to establish assignments of 28 distal marine tephras from three Aegean Sea cores (KL49, KL51 and LC21) to specific volcanic events. Based on interpolation of sapropel core chronologies we provide new eruption age estimates for correlated Santorini tephras, including dates for major Plinian eruptions, Upper Scoriae 1 (80.8±2.9 ka), Vourvoulos (126.5±2.9 ka), Middle Pumice (141.0±2.6 ka), Cape Thera (156.9±2.3 ka), Lower Pumice 2 (176.7±0.6 ka), Lower Pumice 1 (185.7±0.7 ka), and Cape Therma 3 (200.2±0.9 ka), but also for 17 Inter-Plinian events. Older Plinian and Inter-Plinian activity between ~310 ka and 370 ka, documented in the distal terrestrial setting of Tenaghi Philippon (NE Greece), is independently dated by palynostratigraphy and complements the distal Santorini tephrostratigraphic record.